New C++ ABI and -freg-struct-return?

[Joe Buck]

> Is there a formal C/C++ ABI for gnu ix86?

Not really.  There are some notes in the gxxint.texi document --
gcc/cp/gxxint.texi in the GCC distribution -- but they are far
from complete.

> I've been trying to find one for months and have been told by
> knowledgeable people that the only reliable documentation is
> the gcc source code.

It hasn't been a priority to clean this up because a new
ABI is being worked on for GCC 3.0.  This one is intended to be
multiplatform and multivendor (meaning that some compilers besides
GCC will support the same ABI).